A new approach to the life assessment for linear bearings using three-parameter Weibull distribution is discussed and theoretical basic dynamic load ratings are calculated for linear motion ball guides (LMBG) and ball bushes. Life test experiments are also carried out for these two types of linear bearings with varying design features for each type. The concept of a minimum life prior to which there is no failure, is introduced in the analysis of the life test data. The effects of introducing ball cages in LMBGs and rounding of the edges in the case of ball bushes on their lives, basic dynamic load ratings, and the λbm factors are examined. It is observed that compared with a two-parameter Weibull distribution, an analysis based on a three-parameter Weibull distribution clearly reveals the differences in the lives of linear bearings for changes in their designs.

Issue Section:
Technical Papers
Keywords:
machine bearings, life testing, performance evaluation, friction, tribology
Topics:
Stress, Life testing, Bearings
1.
Catalogue: Thomson Ball Bushings for Linear Motion, 1976, Thomson Industries, Manhasset, NY 11030, p. 2.
2.
Weibull, W., 1939, “A Statistical Theory of the Strength of Materials,” IVA Handlingar, Nr. 151, p. 45.
3.
Lundberg, G., and Palmgren, A., 1947, “Dynamic Capacity of Rolling Bearings,” IVA Handlingar, Nr. 196, pp. 12–16.
4.
Tallian
,
T.
,
1962
, “
Weibull Distribution of Rolling Contact Fatigue Life and Deviation Therefrom
,”
ASLE Trans.
,
5
, pp.
183
–
197
.
5.
Shimizu
,
S.
, and
Izawa
,
M.
,
1982
, “
Consideration on Distribution of Rolling Contact Fatigue Life
,”
J. of JSLE, Int. Edition
,
3
, pp.
71
–
76
.
6.
Shimizu
,
S.
, and
Izawa
,
M.
,
1979
, “
Study on the Fatigue Life of Linear Motion Ball Bearing (1st Report)—On the Roll Body Loads in Relation to the Basic Dynamic Load Rating of the Bearing
,”
J. of Prec. Engg.
,
45
,
8
, pp.
981
–
986
(in Japanese).
7.
Shimizu
,
S.
, and
Izawa
,
M.
,
1981
, “
Study on the Fatigue Life of Linear Motion Ball Bearing (2st Report)— On Basic Dynamic Load Rating
,”
J. of Prec. Engg.
,
47
, No.
3
, pp.
277
–
282
(in Japanese).
8.
Izawa
,
M.
, and
Shimizu
,
S.
,
1982
, “
Study on the Fatigue Life of Linear Motion Ball Bearing (3rd Report)—On Reformed Type Bearing
,”
J. of Prec. Engg.
,
48
, No.
10
, pp.
361
–
1366
(in Japanese).
9.
Shimizu
,
S.
, and
Izawa
,
M.
,
1982
, “
Study on Basic Dynamic Load Rating of Linear Motion Ball Bearing
,”
J. of Prec. Engg.
,
48
, No.
10
, pp.
1367
–
1372
(in Japanese).
1.
Shimizu
,
S.
, and
Izawa
,
M.
,
1982
, “
Study on Basic Dynamic Load Rating of Ball Spline
,”
Bull. Japan Society of Prec. Engg.
,
16
, No.
3
, pp.
187
–
188
.
2.
16
, No.
3
, pp.
217
217
.
1.
Izawa
,
M.
, and
Shimizu
,
S.
,
1984
, “
Study on Fatigue Life of Ball Spline
,”
J. of Prec. Engg.
,
50
, No.
12
, pp.
1902
–
1906
(in Japanese).
2.
Shigeo
,
S.
,
1999
, “
Life Distribution of Rolling Machine Elements and S-N Curve
,”
J. of Japanese Society of Tribologist
,
44
, No.
9
, pp.
693
–
699
(in Japanese).
3.
Shimizu, S., Takizawa, H., Sharma, C. S., and Koshiishi, H., 1996, “Study on Tribological Aspects of Linear Motion Ball Guide System—Rolling Contact Fatigue Life Distribution,” Proc. of Int. Trib. Conf., 3, Kimura, Y., ed., JAST, Yokohama, pp. 1369–1374.
4.
Shimizu
,
S.
,
Saito
,
A.
,
Sharma
,
C. S.
, and
Taki
,
Y.
,
1998
, “
Tribological Studies of Linear Motion Ball Guide Systems
,”
STLE Tribol. Trans.
,
41
, No.
1
, pp.
49
–
59
.
5.
S. Shimizu, 1999, Dynamic Capacity of Linear Motion Rolling Guide Elements, The Editorial Committee, Appendix 2–13; Kosaido Insatsu Ltd., Tokyo, Japan.
6.
THK LM System General Catalog, 2000, THK Co., Ltd., Tokyo, Japan, No. 300-E, pp. A-09.
Copyright © 2002
 by ASME
You do not currently have access to this content.